Electric transformer and welding, smelting, and like apparatus.



R. MACK.

ELECTRIC TRANSFORMER AND WELDING, SMELTING, AND LIKE APPARATUS.

APPLICATION FILED SEPT-12,1913.

' Sept.

2 SHEETS I n m mm ww R Patented 17 gm W J R. MACK.

ELECTRIC TRANSFORMER AND WELDING, SMELTING, AND LIKE APPARATUS.

\ APPLICATlON FILED SEPT. 12. 1913.

1,199,092. Patented Sept. 26,1916.

2 SHEETS-SHEET 2.

are a l iiiftf lll hw ELECTRIC TRANSFORMER AND WELDING, SMELTING, AND LIKE APPARATUS.

Specification 01 Letters Fatent.

Patented Sept. 26, 1916..

Application filed September 12, 1913. Serial No. 789,500.

To all whom it may concern.

ing, Smelting, and like Apparatus, of-whiclr the following is a specification.

The object of my invention is to provide a simple, cheap and eflicient single phase, low tension electric transformer.

T0 this, and other subsidiary ends, my invention consists in the combination of elements hereinafter more particularly described and definitely pointed out in the claims.

i In the drawings, Figure 1, is a central sectional view of a transformer embodying the features of my invention, Figs. 2 and 3, are

like views showing modifications of said invention, Fig. 4, is a like view of an apparatus as it would appear when adapted for point-welding purposes, Fig. 5, is a like sectional View showing the device as it would appear when adapted for butt-welding, and Fig. 6, is a cross sectional view of Fig. 5.

Corresponding reference letters in the different figures indicate like parts.

In Fig. 1 a. and b designate the secondary coil formed as a casing consisting of a receptacle and cover 1), 0 is the laminated core and d the primary coil or winding.

In Fig. 2 0 is a central shaft passing through the center of the transformer which can be rotated and serves as a rotating electrode. f shaft e.

In Fig. 3 g is a melting pot of refractory,

but electrically conducting material and h designates the mass to be melted.

Fig. 1 shows the complete transformer and in Figs. 2 and 3 the primary coil and the laminated core are omitted. The path of the welding current in the secondary coil is indicated in Fig. 1 by the broken line. The poles of the secondary conductor, in the embodiment of the invention illustrated in Fig. 1, are indicated by the plusand minus signs at which place the welding apparatus can be connected.

In Fig. 2 e and b are the poles or elecis a belt pulley for driving the trodes of the secondary conductor. In this construction, the central part a, is formed to constitute a bearing for the rotary electrode c, which is adapted to be driven from the belt pulley f. The advantage of this, among other things, is that superfluous connections are eliminated and the length of the secondary conductor may be reduced to the utmost limit. In practice it frequently happens that for the continuous welding of certain objects, or welding which is intermittent or continuous, a rotary electrode is required, and in such a case the arrangement of the secondary conductor is of great importance because by this means the sum of the resistances in thesecondary conductor circuit is reduced to the minimum owing to the absence of joints and intermediate elements. The shaft 6 is wholly or partially an electrical conductor and can be driven by the belt pulley f or other appropriate transmission means.

Fig. 3 illustrates the invention in its simplest form as a meltin furnace, as the secondary circuit is closediy the material of the melting pot which is of higher resistance than the object to be melted, as in Figs. 1 and 2. It will be understood that by providing a suitablespace between the melting pot and the primary winding, and by air or water cooling, the primary winding can be ade uately protected from the smelting heat. ere also the melting pot can be provided in the usual manner with. a pouring spout and the casing with trunnions so that the whole can be rotated for pouring the molten mass.

If desired, the complete transformer can be arranged upon an under frame on legs or the like, in order to facilitate its manipula- .tion.

In the drawing, the apparatus illustrated is of circular form, but this is not indispensable or necessarily advantageous. Cases may arise-in which the secondary winding a, the laminated core 0 and the primary winding al must be given a rectangular form. The outer wall of the secondary coil can also advantageously be provided with vents of I appropriate size for air cooling as shown at a Fig. 3. 3

F'gs. 4 and 5 and 6 illustrate practical constructional forms of the transformer hereinbefore described in connection with a point and a butt-joint welding apparatus.

In the several figures, a and b, as before, represent the secondary winding, which, at the same time, forms a casing," c is the laminated core and d the primary winding; 6 is the lower electrode arm, which, in; point welding machines, is usually stationary, and f is the upper electrode arm rotatable about the shaft f in the bearing f p i designates insulatin material serving to insulate the upper'eFectric arm f from the cover forming part of the secondary winding 12.

k is a flexible conductor between 7 and a and consists of a plurality of bent strips of conductingmaterlal with the object of enabling the arm f to be easily displaced while at the same time affording a good metallic connection.

l is the under frame of the transformer which in the present case consists of two standards connected together nearthe floor by a tie rod m.

n is a pedal for actuating the apparatus cordmected with the lever electrode f by a r0 0.

p is a pivot fixed to the lever f engaging a slot q in the rod 0.

r and s are members carrying the primary contacts, etc., which are insulated one from the other, and from the said members so that they are not in metallic contact. While the member 1' is freely movable in a vertical direction on the rod 0 the member s is socured to the rod 0 by a pin so that the member s is able to rock on the rod 0.

a is a spring arranged between members 1' and s, in order, on the onehand to hold the contact pieces t at a suitable distance apart when the apparatus is inoperative,

and on the other hand, to press the Welding electrodes 4) together. It is desirable that they should be brought together before closing the electric circuit therewith. When 'the operator presses his foot upon the treadle the first action is to cause them to contact, after which, a further pressure acts to compress the spring until the electric circuit is closed.- 7

In Fig. 5 w designates clamps for holding the articles to be welded such as bars at for example. These clamps w also form the poles of the secondary C01l. y is a threaded spindle mounted on a fixed ortion of the casing, and provided with a and wheel so that by means of a projection on the upper portion or cover 6 which is here formed as a support (Figs. 5 and 6) the latter can be shifted for example when the heated work is to be moved mto the welding position. 2 are guide bars for guiding the cover 6 In the embodiment of the invention illustrated in Fig. 4 the complete transformer 1s combined with a point welding apparatus.

When the pedal n is depressed, the-primary I slots similar to the slots used in connecting a machine tool to a bed plate for the purose of enabling the arm e to be adjusted orizontall and vertically in a convenient manner. he under frame l is fixed directlyto the bottom of the casing.

The opening of the electrodes '0 takes place automatically under the influence of gravity after the pedal has been released. A weight or spring can, however, be employed for this purpose if desired.

f necessary the welding apparatus can also be driven by a motor or the like; in other words the examples here given are illustrated diagrammatically only.

Figs. 5 and 6 illustrate a constructional form of the machine combined with a butt welding apparatus. Here also the path of the secondary current is indicated by the arrows. Gases may arise in which a 10 form of casing is desirable, but this-wou ld give rise to unfavorable dimensions as regards the constructions hitherto adopted for the laminated transformer coils. Accordingly instead of a single central conductor a, two or more such conductors and an equal number of transformer coils with primary windings may be arranged in a common casing and connected in parallel.

What I"claim and desire to secure by Letters Patent is 1. A single phase low tension transformer for welding, melting or like purposes, comprising a secondary winding in the form of a protective casing, closed within said casing and a core integral with saidc-asing, said primary winding being interposed between said core and casing.

2. A single phase low tension transformer for the purpose specified, comprising, in combination, primary and secondary windings, the latter constitutin a protective casing for the former which is inclosed therein, said casing being provided with a removable cover and a central core, each forming a art thereof.

3. A sing e phase low tension transformer for the purpose specified com rising a secondary winding in the form 0 a casmg,

a primary winding ining part of the winding, and a primary 10 winding and core in said casing.

In testimony whereof I have affixed my signature in presence of two witnesses.

RICHARD MACK.

Witnesses WoLnnMAn HAUr'r, An'rmm Sonnommn. 

